1. Field of the Invention
The present invention relates to a thin film storage container which has an improved sealability for sealing a cover and a container main body and an improved detachability.
2. Description of the Related Art
Generally, there is known, as a thin film storage container, a container for storing and transporting semiconductor silicon wafers. As for the wafer storage and transport container, it is important to transport the container while keeping an interior of the container clean in order to prevent contamination of surfaces of the wafers contained therein. To this end, the interior of the container is sealed. That is, a cover member is fixed to a container main body, thereby sealing an interior of the container main body. The sealing of the cover member and the container main body is normally performed by providing a sealant between the cover member and the container main body. This sealant, which is attached to a peripheral edge of the cover member, and which elastically abuts against the container main body using a force of pressing the cover member against the container main body, seals the interior of the container main body.
Since the thin film storage container has a small gap between the cover member and the container main body, the sealant is substantially exposed to the outside. For this reason, a contaminant sometimes enters the container from the outside. This contaminant also enters into an abutment portion between the sealant and the container main body. If the cover member is attached to the container main body, the contaminant does not pose a serious problem. However, when the cover member is detached from the container main body, a problem occurs. Namely, when the cover member is detached from the container main body, an internal pressure of the container main body is temporarily negative, so that the outside air flows into the container main body from the gap formed in the abutment portion between the sealant and the container main body. If the contaminant enters the abutment portion between the sealant and the container main body, the contaminant disadvantageously enters the container main body.